Billy Joel (b. 1949) appeared on Sesame Street during Season 20 (1988), singing "Just the Way You Are" with Marlee Matlin for Oscar the Grouch. He also sang "The Alphabet Song" to the Anything Muppets on the program.
His 1982 song "Pressure" references Sesame Street.
In the video Do the Alphabet, part of Big Bird's method of learning the alphabet is impersonating Joel and his performance of "The Alphabet Song" follows. Baby Bear dons a par of sunglasses and is given a piano to replicate this appearance.